Hell on earth: The rampaging super swarms of birds and insects invading suburbia

At what looks like the mouth of hell, a terrifying swarm of locusts devastates crops, eating everything in its path. On the other side of the Atlantic, clouds of 'smoke' rise from Africa's Lake Victoria and hover over the water.

On closer inspection, these apparitions are a blinding, choking maelstrom of midges sparked into existence by the continent's wet season.

Great swarms are one of nature's most bewitching creations. Made up of millions or even billions of creatures, they possess an intelligence that is beyond scientific understanding and can also be startlingly beautiful.

Destructive: A swarm of mayflies has its own form of intelligence beyond scientific understanding

Now, a new BBC documentary explores the intelligence behind such mass invasions and reveals that, by communicating instinctively as one giant organism, swarms are able to accomplish far more than the sum of their parts.

'Nature has evolved two ways of creating intelligent behaviour,' says John Downer, the producer of the series Swarm. 'One is to develop large, sophisticated brains in individual organisms, such as humans, and the other is millions of smaller brains, which communicate with each other inside a colony - the superswarm.'

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Downer is the award-winning creator of such acclaimed TV series as SuperNatural and Weird Nature. Now, he ventures into the very heart of the swarms, with incredible high-speed shots from inside the fantastic colonies, revealing just how the milling myriads view our world.

Locusts are perhaps the most destructive of all swarms. An average swarm contains billions of locusts, and the biggest outbreaks can infest half a continent. They invade one-fifth of the world's land surface, affecting one-tenth of the planet's population and leaving starvation in their wake. Little wonder that they were one of the ten plagues that descended on Egypt in the Bible.

A swarm of locusts is able to fly in perfect formation by keeping a set distance from each other - sometimes wingtip to wingtip and at other times, a foot apart - and by synchronising their wing beats to reduce turbulence. They even have anti-crash sensors, fine hairs on their heads, to avoid collisions and react six times faster than a human pilot to obstacles in their path.

They eat their own weight in food in a day, and a large swarm can get through 200,000 tonnes - enough to feed half a billion people.

On the other side of the world, in Africa, the rainy season triggers the biggest swarms of midges on Earth to rise from Lake Victoria. The locals make best use of this blight, however, by catching them in nets and turning them into nutritious fly-burgers - each one contains half a million flies and is packed with seven times more protein than a beef burger.

Buzz off: Professor Norman Gary engulfed by bees as he carries out research into the species which can be fatal if they form a swarm

Unfortunately, urbanisation has confused some creatures, causing unforeseen problems for mankind. In the US, for instance, within a single night - often on Independence Day, 4 July - mayfly larvae hatch from the surface of America's lakes and waterways.

As soon as the temperature of the water reaches 63F, the larvae instinctively aim for the moon and then mate in mid-air, before falling back to earth to die. More than 20 trillion mayflies emerge in a single night.

The problem is that the mayflies cannot tell the difference between the moon and a streetlight, and, in the morning, some towns need to use snowploughs to shift the tons of tiny bodies from the streets.

Like something out of a horror movie, some swarms invade only once in a generation - in the case of so-called periodic cicadas, this is every 17 years. They live deep underground across vast areas of North America, and emerge to mate.

The theory is that they do this to confuse predators - no predator lives long enough to pass on the knowledge of the next emergence to their offspring. The latest alien invasion took place in the state of Ohio in July, when ten billion cicadas dug themselves to the surface overnight.

Sadly, many more found themselves entombed under the concrete of ever-expanding cities such as Cincinnati - and died before ensuring the continuation of the next generation.

Those that make it to the surface then get involved in a noisy courtship ritual. Because all the males vibrate a drum-like organ in their bodies, the combined racket reached 100 decibels - far louder than a jet flying overhead. Finally, having met and mated, the cicadas laid their eggs in tree bark and, job done, dropped dead in their millions.

Another massive clean-up for the residents of suburbia. But it's not just Americans who have such a huge operation on their hands after a swarm.

In Rome, which has inexplicably become the starling capital of the world, ten million of them flock together to create the most astonishing aerial display in nature. The mesmeric waves they form in the sky act as a beacon to others entering the city.

To create such perfect synchronicity - the flock contract, expand and even split, continuously changing density and structure - the birds must react 13 times faster than humans. And it has recently been proved that each starling maintains perfect formation by keeping exactly seven other birds in its sight at all times - and will stick to its chosen seven wing-mates irrespective of distance.

The downside of being able to witness this stunning aerial ballet, is starling droppings on a massive scale throughout central Rome.

It's not very often that a man will volunteer to be covered in bees, but Norman Gary, a Californian professor of entomology, agreed to do so for the documentary. The world's leading expert on bees, the professor developed a unique formula of queen bee pheromone that he uses to lead and control an entire swarm of hundreds of thousands of bees.

With this chemical - and an understanding of their behaviour - he can make an entire swarm cover his body like a living suit without suffering a single sting. The bees actually think he is their queen, so smother his body to protect him. But even an expert such as professor Gary wouldn't tangle with killer bees, which were accidentally created in Brazil in 1957 by crossing honey bees with aggressive African bees. Since then, they have spread northwards as far as the southern states of America.

A killer bee's sting is no worse than that of a honey bee, but hundreds will sting at any one time - and it's this mass assault that makes them dangerous. Killer bees once halted an international football match in Costa Rica, sending players diving to the ground and spectators running for their lives.

Most of us don't even notice ants as we go about our daily lives, but we may soon find there's rather more of them around than before, as the UK is on the verge of an ant invasion.

The alien black ant, originally from south-east Europe, is set to push out our domestic black ant and start to 'farm' aphids in our own back gardens. Says John Downer, 'Ants are the perfect examples of the mysterious "swarm intelligence", since they act like a giant organism controlled by a single brain.

'Scientists have shown that ants have recognisable personalities. Each individual uses its own senses to react in different ways. Some are scared, some brave; other are busy or lazy, and these interpretations are fed back to others in the swarm via pheromones. Each ant can detect every other ant's pheromones, so the whole colony knows what's going on everywhere at once. The individual ants react in the same way as nerve cells in a brain - so combine their collective senses and a colony acts like a giant brain.'

So that's where the Star Trek producers got the idea for the Borg from.